How to setup up a fretless bass with a zero fret.

I've installed a fretless Moses neck on my Steinberger, and it's got a zero fret. I believe that the zero fret is too high, and I'm not sure about my neck relief; there's about 2/32nds of an inch space between the fingerboard and the bottom of the E string when fretted at the first and 24 position. Everything feels just slightly high - what's the proper order for me to set this thing up? I know that one adjustment will affect the other; so what do I fix first? How low should I grind this zero fret down (specs please, if possible)? Should the neck be dead straight, or is this the proper amount of relief?

You should set the truss rod first, because that's the one aspect that you can set up without the other parts of the setup affecting it. Since you press the string against the fingerboard at both ends, the height before pressing it down won't matter.

After that, you should probably set the action. And intonation. Maybe set the pickup height too, so it's just how you'd be playing it. Play for a while, and see if the zero fret bothers you. If it does, then you should start thinking about lowering it.

I have those. I've been working on grinding the fret down with a fret file - very slowly. It seems to be coming along pretty well; I've ground the zero fret down by about halfway, and it still feels slightly high. I'm gauging how low it should be by fretting the string at the 3rd position, and measuring the distance between the fretboard and the 1st position. I've still got about 1/32" to 2/32" under there - I'm wondering how far I should go before it's too far.